A. Field of the Invention
The present invention relates to an exercise device. More particularly, the present invention relates to safe impact ball for exercising hand grip as well as practicing ball skill between players.
B. Description of the Prior Art
Traditional balls used in recreational games and competition sports are closed spheres or ovoids inflated with air. Besides being hit, kicked, thrown and rolled between multiple players, when the balls are used as an individual's exercise tool they can improve the exerciser's muscle power, responsiveness and speed through catching and squeezing among other activities.
For this purpose, different materials have been introduced to simulate the flexibility, bounce or texture of the conventional inflated balls in the category of novelty balls. They are gel-filled squeeze balls, ball shaped foam or simply a tennis ball that yields to a rather high strength hand squeeze. Gelatinous balls and foam balls have been considered more desirable in that they can be made solid simply by pouring the respective materials into a round mold cavity or through cutting and are carefree from maintaining a hollow center to fill.
Gel-filled balls in the size of a baseball for example may provide an effective resistance to make a good grip exerciser, but in the hands of young ones they could easily become throwing objects that may hit someone hard resulting in injury. In contrast, a solid foam ball may be almost as light as air due to its perforated structure but lacks the material resistance to give a meaningful muscular improvement to the exerciser. Also, foam balls are normally made into a larger volume to gain a throwing momentum for old and new ball throwing games with less concern for injuries.
Furthermore, conventional squish balls locally yield to applied forces but do not actually change their volumes in an intuitive manner to effect shrinkage and expansions in response to contracting and spreading hands during exercise.
Therefore, an object of the present invention is to provide a new concept of a hand exercise device with the curvature of a ball and the lightness of thin layers but carries the resistance of an inflated ball to interact with hand muscles.
Another object of the present invention is to provide a low cost exerciser device made of a single piece of thin expanded sheet molded into a spherical shrinkable surface.